Accelerated Carbonation
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Estudo experimental do fluxo de umidade em argamassas de cal aérea
RESUMO Uma parte significativa do património histórico construído ao redor do mundo é constituída de alvenaria estrutural, com juntas preenchidas com argamassa. Nesses sistemas estruturais, a argamassa usualmente representa uma parcela pequena/moderada do volume total da estrutura, no entanto, a argamassa é reconhecida como a principal fonte de movimen
Matéria (Rio J.). Publicado em: 25/11/2019
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2. Durability of Concrete After Fire Through Accelerated Carbonation Tests
Degradation of mechanical properties and durability of reinforced concrete structures occur when they are subjected to fire situations, depending on the characteristics of the material, fire duration and the ways of fire extinguishing. Mechanical properties such as compressive strength, tensile strength and elasticity modulus are some examples of typically a
Mat. Res.. Publicado em: 18/07/2019
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3. Efeito da adição de fibras híbridas na durabilidade de compósitos cimentícios avançados em ambientes úmidos e agressivos
ABSTRACT Reactive powder concrete (RPC) is one type of advanced cementitious composite that has been increasingly used. Its high mechanical strength enables the application of the composite in bolder structures. Considering its recent history of use, there is a lack of knowledge about this materials durability. Therefore, this paper aimed to evaluate the beh
Matéria (Rio J.). Publicado em: 18/10/2018
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4. Estimativa da carbonatação natural de materiais cimentícios a partir de ensaios acelerados e de modelos de predição / Estimate of natural carbonation of cement materials based on accelerated tests and prediction models
A carbonatação, fenômeno físico-químico de reação entre o dióxido de carbono da atmosfera e os produtos da hidratação do cimento, reduz a alcalinidade do concreto, destruindo a película passivadora que envolve o aço, podendo dar condições para a iniciação da corrosão das armaduras. Devido ao tempo requerido para que a reação ocorra em cond
Publicado em: 2011
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5. CARBONATAÇÃO NATURAL DE PROTÓTIPOS DE CONCRETO COM CINZA DE CASCA DE ARROZ SEM MOAGEM / NATURAL CARBONATION IN CONCRETE PROTOTYPES WITH NON-GROUND RICE HUSK ASH
Cement is the construction building material with higher responsibility by carbon dioxide emission of all industrial human activities, besides be a considerably expensive material, more than the rice husk ash in nature. Environmental benefits are generated in its utilization, because rice husk ashes are industrial process residues of the grain processing, th
Publicado em: 2010
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6. Contribution to the development of performance specifications for concretes containing blast furnace slag / Contribuição ao desenvolvimento de especificações por desempenho para concretos com escoria de alto-forno
In 2008 alone, the annual steel production in Brazil was around 31 million tons. The steel production process generates an average of 500 kg of residues and co-products per ton of steel. From this total, 70% corresponds to the slags. Although investigating the increase of blast furnace slag use is of extreme importance for the concrete and steel industries s
Publicado em: 2010
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7. Sisal organosolv pulp as reinforcement for cement based composites
The present work describes non-conventional sisal (Agave sisalana) chemical (organosolv) pulp from residues of cordage as reinforcement to cement based materials. Sisal organosolv pulp was produced in a 1:1 ethanol/water mixture and post chemically and physically characterized in order to compare its properties with sisal kraft pulp. Cement based composites
Materials Research. Publicado em: 2009-09
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8. Avaliação das propriedades de transporte de massa contendo adições minerais / Evaluation of the mass transport containing mineral admixtures
The durability of reinforced concrete structures is damaged by the degrading action of the penetration of substances in the form of gases, vapors and liquids through the pores and cracks. It is known that water both in its pure form or containing dissolved ions such as chloride, sulphate, carbon dioxide or oxygen ions, can compromise the durability of concre
Publicado em: 2009
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9. CARBONATAÇÃO EM CONCRETO COM CINZA DE CASCA DE ARROZ SEM MOAGEM / CONCRETE CARBONATION WITH UNGROUND RICE HUSK ASH
This research is part of a project that aimed to evaluate the technical viability of the use of unground (in natura) residual Rice Husk Ash (RHA), without grinding, for structural concrete. The present work investigated the evaluation of the depth and the determination of the carbonation coefficients for concrete with the addition of 15% and 25% residual RHA
Publicado em: 2008
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10. STUDY OF CARBONATION OF THE COVERCRETE LAYER OF PROTOTYPES OF CONCRETE WITH HIGH ADDITIONS CONTENTS AND LIME HYDRATED / ESTUDO DA CARBONATAÇÃO DA CAMADA DE COBRIMENTO DE PROTÓTIPOS DE CONCRETO COM ALTOS TEORES DE ADIÇÕES MINERAIS E CAL HIDRATADA
In this study deals the covercrete structural concrete layer with the use of hydrated lime in substitution in mass of the sand in ternary mixture of 70% of blast-furnace slag, 20%-fly ash and 10% of cement CPV-ARI (EVC) in comparison to reference with 100% CPV-ARI (R) and other ternary mixture of 70%-ground granulated blast-furnace slag, 20%-fly ash and 10%-
Publicado em: 2008
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11. CARBONATION AND CAPILLARY ABSORPTION IN CONCRETES OF WHITE PORTLAND CEMENT WITH HIGH CONTENTS OF BLAST FURNACE SLAG AND CHEMICAL ACTIVATORS / CARBONATAÇÃO E ABSORÇÃO CAPILAR EM CONCRETOS DE CIMENTO PORTLAND BRANCO COM ALTOS TEORES DE ADIÇÃO DE ESCÓRIA DE ALTO FORNO E ATIVADOR QUÍMICO
The carbonation phenomenon, reaction between CO2 from the atmosphere in the presence of humidity with the Portland cement hydration products, induces pH reduction to levels that can cause the elimination of steels protective layer, enabling the corrosion mechanism of the steel structure to start.. This is one of the main pathologies in the reinforced concret
Publicado em: 2008
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12. Contribuição ao estudo da carbonatação do concreto com adição de sílica ativa em ambiente natural e acelerado
Devido à preocupação com a durabilidade das estruturas de concreto armado surgiram novas linhas de pesquisa destacando-se, dentre elas, a previsão de vida útil. Estes estudos deram origem a diversos modelos que tentam estabelecer o comportamento do concreto quando exposto a ambientes agressivos durante um determinado período. Existem várias maneiras d
Publicado em: 2007